diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/libexpr/lexer.l | 15 | ||||
| -rw-r--r-- | src/libexpr/nixexpr-ast.def | 3 | ||||
| -rw-r--r-- | src/libexpr/parser.y | 107 |
3 files changed, 122 insertions, 3 deletions
diff --git a/src/libexpr/lexer.l b/src/libexpr/lexer.l index 9f0f0b335f57..23a14324f32c 100644 --- a/src/libexpr/lexer.l +++ b/src/libexpr/lexer.l @@ -4,6 +4,7 @@ %x STRING +%x IND_STRING %{ @@ -122,6 +123,14 @@ inherit { return INHERIT; } <STRING>\" { BEGIN(INITIAL); return '"'; } <STRING>. return yytext[0]; /* just in case: shouldn't be reached */ +\'\'(\ *\n)? { BEGIN(IND_STRING); return IND_STRING_OPEN; } +<IND_STRING>([^\$\']|\$[^\{\']|\'[^\'])+ { + yylval->t = makeIndStr(toATerm(yytext)); + return IND_STR; + } +<IND_STRING>\$\{ { BEGIN(INITIAL); return DOLLAR_CURLY; } +<IND_STRING>\'\' { BEGIN(INITIAL); return IND_STRING_CLOSE; } +<IND_STRING>. return yytext[0]; /* just in case: shouldn't be reached */ {PATH} { yylval->t = toATerm(yytext); return PATH; /* !!! alloc */ } {URI} { yylval->t = toATerm(yytext); return URI; /* !!! alloc */ } @@ -148,4 +157,10 @@ void backToString(yyscan_t scanner) BEGIN(STRING); } +void backToIndString(yyscan_t scanner) +{ + struct yyguts_t * yyg = (struct yyguts_t *) scanner; + BEGIN(IND_STRING); +} + } diff --git a/src/libexpr/nixexpr-ast.def b/src/libexpr/nixexpr-ast.def index c7029e927047..a06d34311ae1 100644 --- a/src/libexpr/nixexpr-ast.def +++ b/src/libexpr/nixexpr-ast.def @@ -46,6 +46,9 @@ Int | int | Expr | Str | string ATermList | Expr | Str | string | Expr | ObsoleteStr +# Internal to the parser, doesn't occur in ASTs. +IndStr | string | Expr | + # A path is a reference to a file system object that is to be copied # to the Nix store when used as a derivation attribute. When it is # concatenated to a string (i.e., `str + path'), it is also copied and diff --git a/src/libexpr/parser.y b/src/libexpr/parser.y index 82b24cd07379..cd3ba88aa658 100644 --- a/src/libexpr/parser.y +++ b/src/libexpr/parser.y @@ -68,9 +68,100 @@ static Expr fixAttrs(int recursive, ATermList as) } +static Expr stripIndentation(ATermList es) +{ + if (es == ATempty) return makeStr(""); + + /* Figure out the minimum indentation. Note that by design + whitespace-only final lines are not taken into account. (So + the " " in "\n ''" is ignored, but the " " in "\n foo''" is.) */ + bool atStartOfLine = true; /* = seen only whitespace in the current line */ + unsigned int minIndent = 1000000; + unsigned int curIndent = 0; + ATerm e; + for (ATermIterator i(es); i; ++i) { + if (!matchIndStr(*i, e)) { + /* Anti-quotations end the current start-of-line whitespace. */ + if (atStartOfLine) { + atStartOfLine = false; + if (curIndent < minIndent) minIndent = curIndent; + } + continue; + } + string s = aterm2String(e); + for (unsigned int j = 0; j < s.size(); ++j) { + if (atStartOfLine) { + if (s[j] == ' ') + curIndent++; + else if (s[j] == '\n') { + /* Empty line, doesn't influence minimum + indentation. */ + curIndent = 0; + } else { + atStartOfLine = false; + if (curIndent < minIndent) minIndent = curIndent; + } + } else if (s[j] == '\n') { + atStartOfLine = true; + curIndent = 0; + } + } + } + + /* Strip spaces from each line. */ + ATermList es2 = ATempty; + atStartOfLine = true; + unsigned int curDropped = 0; + unsigned int n = ATgetLength(es); + for (ATermIterator i(es); i; ++i, --n) { + if (!matchIndStr(*i, e)) { + atStartOfLine = false; + curDropped = 0; + es2 = ATinsert(es2, *i); + continue; + } + + string s = aterm2String(e); + string s2; + for (unsigned int j = 0; j < s.size(); ++j) { + if (atStartOfLine) { + if (s[j] == ' ') { + if (curDropped++ >= minIndent) + s2 += s[j]; + } + else if (s[j] == '\n') { + curDropped = 0; + s2 += s[j]; + } else { + atStartOfLine = false; + curDropped = 0; + s2 += s[j]; + } + } else { + s2 += s[j]; + if (s[j] == '\n') atStartOfLine = true; + } + } + + /* Remove the last line if it is empty and consists only of + spaces. */ + if (n == 1) { + unsigned int p = s2.find_last_of('\n'); + if (p != string::npos && s2.find_first_not_of(' ', p + 1) == string::npos) + s2 = string(s2, 0, p + 1); + } + + es2 = ATinsert(es2, makeStr(s2)); + } + + return makeConcatStrings(ATreverse(es2)); +} + + void backToString(yyscan_t scanner); +void backToIndString(yyscan_t scanner); + - static Pos makeCurPos(YYLTYPE * loc, ParseData * data) { return makePos(toATerm(data->path), @@ -121,10 +212,11 @@ static void freeAndUnprotect(void * p) %type <t> start expr expr_function expr_if expr_op %type <t> expr_app expr_select expr_simple bind inheritsrc formal -%type <ts> binds ids expr_list formals string_parts -%token <t> ID INT STR PATH URI +%type <ts> binds ids expr_list formals string_parts ind_string_parts +%token <t> ID INT STR IND_STR PATH URI %token IF THEN ELSE ASSERT WITH LET IN REC INHERIT EQ NEQ AND OR IMPL %token DOLLAR_CURLY /* == ${ */ +%token IND_STRING_OPEN IND_STRING_CLOSE %nonassoc IMPL %left OR @@ -199,6 +291,9 @@ expr_simple else if (ATgetNext($2) == ATempty) $$ = ATgetFirst($2); else $$ = makeConcatStrings(ATreverse($2)); } + | IND_STRING_OPEN ind_string_parts IND_STRING_CLOSE { + $$ = stripIndentation(ATreverse($2)); + } | PATH { $$ = makePath(toATerm(absPath(aterm2String($1), data->basePath))); } | URI { $$ = makeStr($1, ATempty); } | '(' expr ')' { $$ = $2; } @@ -219,6 +314,12 @@ string_parts | { $$ = ATempty; } ; +ind_string_parts + : ind_string_parts IND_STR { $$ = ATinsert($1, $2); } + | ind_string_parts DOLLAR_CURLY expr '}' { backToIndString(scanner); $$ = ATinsert($1, $3); } + | { $$ = ATempty; } + ; + binds : binds bind { $$ = ATinsert($1, $2); } | { $$ = ATempty; } |